The Russian president said his priority was to protect citizens living abroad, regardless of where they were.

That could include action to safeguard Russians living in the North African state of Libya, which has been ravaged by violent Islamic extremism since the fall of dictator Colonel Gaddafi.

Speaking at the fifth World Congress of Compatriots in Moscow, Mr Putin said: "People who are not in Russia due to various reasons should be firmly sure: we will always protect your interests.

"Moreover, in difficult and crisis situations, such as in Libya, Syria or Yemen."

Russia has been providing humanitarian aid to Yemen since the outbreak of the civil war in March.

A Russian cargo plane delivering humanitarian aid to Yemen

The Arab state has suffered from internal conflict between Saudi-backed separatists and forces loyal to the government of Abd Rabbuh Mansur Hadi based in the south, and Iran-backed Houthi forces and those loyal to the former president Ali Abdullah Saleh.

Russia is allied to Iran as the main backers of President Bashar al-Assad in the conflict in Syria.

Aid arriving in Yemen included fresh drinking water

The United Nations (UN) estimates around 5,000 people have been killed in the conflict since March, more than half of them civilians.